According to the difference in working principles, the wet shotcrete machine can be divided into three types: pumping type, pneumatic type and HSP type. About these three types, the author will briefly discuss them!
First, the pump type wet shotcrete machine
1. The plunger pump wet shotcrete machine uses the plunger concrete pump as the basic body of the concrete wet shotcrete machine. A nozzle is installed at the outlet of the conveying pipe and compressed air is passed in to spray the concrete out. This type of wet shotcrete machine is generally bulky but has a long conveying distance.
Second, pneumatic wet shotcrete machine
Pneumatic wet shotcrete machine uses compressed air to convey materials in a hose in the form of "thin flow" to the nozzle and directly ejects it. This type of wet shotcrete machine consists of two tanks side by side, one spraying and one stocking There is a horizontal spiral conveyor at the bottom of the tank. Compressed air is introduced into the spray tank. The wet mix is fed into the conveying pipe through the spiral. At the nozzle, the mix is sprayed out by the compressed air introduced by the air ring. The disadvantage of this wet shotcrete machine is that it is more troublesome to feed into the tank, and the cleaning of the tank is also inconvenient.
3. HSP Wet Shotcrete Machine
HSP wet shotcrete machine is a new type of high-efficiency shotcrete machine, mainly used for spraying wet concrete. It can make the mixture mix evenly, and the water-cement ratio can be controlled accurately. Small, good concrete homogeneity and high strength. The machine has a reasonable structure, stable performance, convenient operation and maintenance, and long service life. It is widely used in iron (public) road tunnels, subways, hydropower projects, underground projects, and shotcrete construction operations in mine shafts.
